1. Field of the Invention
The present invention relates generally to ankle foot orthotic foot braces, or AFO braces.
2. Related Art
Ankle foot orthotic braces, or AFO braces, have been developed to deal with plantar flexion and dorsiflexion problems, such as from ankle injuries. AFO's are used to improve gait and stability. Some AFO's are plastic and can fit inside a shoe. Other AFO's have double upright metal braces that are built into the shoe itself, or attached to a sole.
Typically, AFOs are either rigid and unbending, or have a hinge at the ankle. Rigid AFO's are designed to keep the foot in the proper position and are often used while the individual is asleep. Hinged AFO's, on the other hand, allow for both free plantar flexion (downward motion) and free dorsiflexion motion (upward motion). Hinged AFO's can also allow free dorsiflexion motion but prevent plantar flexion motion by incorporating a stop in the brace. Some hinged AFO's have a spring to assist in dorsiflexion motion to help lift a dropped foot when a person walks.
While such springs assist in lifting a dropped foot when after a step is completed and the foot is being moved to the next step, such springs can also interfere with finishing a step because the spring tends to pull the toe upward when the user is naturally pushing downward with the toe. Furthermore, such spring assist AFO's create a very unnatural heel strike or downward movement of the foot because the toe is biased into an upward position, resulting in a very hard heel strike.